const UnicodeTrie = require('unicode-trie')
const base64 = require('base64-js');

import classes from './classes'
const { BK, CR, LF, NL, CB, BA, SP, WJ,
  // SP, BK, LF, NL,
  AI, AL, SA, SG, XX, CJ, ID, NS} = classes;

import paris from './pairs'
const { DI_BRK, IN_BRK, CI_BRK, CP_BRK, PR_BRK, pairTable} = paris

// let base64String = require('fs').readFileSync(__dirname + '/classes.trie', 'base64')
let base64String = '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'
const data = base64.toByteArray(base64String)
const classTrie = new UnicodeTrie(data)

const mapClass = function (c) {
  switch (c) {
    case AI:
      return AL
    case SA:
    case SG:
    case XX:
      return AL
    case CJ:
      return NS
    default:
      return c
  }
}

const mapFirst = function (c) {
  switch (c) {
    case LF:
    case NL:
      return BK
    case CB:
      return BA
    case SP:
      return WJ
    default:
      return c
  }
}

class Break {
  constructor(position, required = false) {
    this.position = position
    this.required = required
  }
}

class LineBreaker {
  constructor(string) {
    this.string = string
    this.pos = 0
    this.lastPos = 0
    this.curClass = null
    this.nextClass = null
  }

  nextCodePoint() {
    const code = this.string.charCodeAt(this.pos++)
    const next = this.string.charCodeAt(this.pos)

    // If a surrogate pair
    if ((0xd800 <= code && code <= 0xdbff) && (0xdc00 <= next && next <= 0xdfff)) {
      this.pos++
      return ((code - 0xd800) * 0x400) + (next - 0xdc00) + 0x10000
    }

    return code
  }

  nextCharClass() {
    return mapClass(classTrie.get(this.nextCodePoint()))
  }

  nextBreak() {
    // get the first char if we're at the beginning of the string
    if (this.curClass == null) {
      this.curClass = mapFirst(this.nextCharClass())
    }

    while (this.pos < this.string.length) {
      this.lastPos = this.pos
      const lastClass = this.nextClass
      this.nextClass = this.nextCharClass()

      // explicit newline
      if ((this.curClass === BK) || ((this.curClass === CR) && (this.nextClass !== LF))) {
        this.curClass = mapFirst(mapClass(this.nextClass))
        return new Break(this.lastPos, true)
      }

      // handle classes not handled by the pair table
      let cur
      switch (this.nextClass) {
        case SP:
          cur = this.curClass
          break
        case BK:
        case LF:
        case NL:
          cur = BK
          break
        case CR:
          cur = CR
          break
        case CB:
          cur = BA
          break
      }

      if (cur != null) {
        this.curClass = cur
        if (this.nextClass === CB) {
          return new Break(this.lastPos)
        }
        continue
      }

      // if not handled already, use the pair table
      let shouldBreak = false
      switch (pairTable[this.curClass][this.nextClass]) {
        case DI_BRK: // Direct break
          shouldBreak = true
          break

        case IN_BRK: // possible indirect break
          shouldBreak = lastClass === SP
          break

        case CI_BRK:
          shouldBreak = lastClass === SP
          if (!shouldBreak) {
            continue
          }
          break

        case CP_BRK: // prohibited for combining marks
          if (lastClass !== SP) {
            continue
          }
          break
      }

      this.curClass = this.nextClass
      if (shouldBreak) {
        return new Break(this.lastPos)
      }
    }

    if (this.pos >= this.string.length) {
      if (this.lastPos < this.string.length) {
        this.lastPos = this.string.length
        return new Break(this.string.length)
      } else {
        return null
      }
    }
  }
}

export default LineBreaker;